Death by black hole in small galaxy?

Jan 08, 2014

A dwarf galaxy is located in the galaxy cluster Abell 1795. Credit: X-ray: NASA/CXC/Univ. of Alabama/W.P.Maksym et al & NASA/CXC

(Phys.org) —A bright, long-duration flare may be the first recorded event of a black hole destroying a star in a dwarf galaxy. The evidence comes from two independent studies using data from NASA's Chandra X-ray Observatory and other telescopes.

As part of an ongoing search of Chandra's archival data for events signaling the disruption of stars by massive black holes, astronomers found a prime candidate. Beginning in 1999, an unusually bright X-ray source had appeared in a dwarf galaxy and then faded until it was no longer detected after 2005.

"We can't see the star being torn apart by the black hole," Peter Maksym of the University of Alabama in Tuscaloosa, AL, who led one of the studies, "but we can track what happens to the star's remains, and compare it with other, similar events. This one fits the profile of 'death by a black hole.'"

Scientists predict that a star that wanders too close to a giant, or supermassive, black hole could be ripped apart by extreme tidal forces. As the stellar debris falls toward the black hole, it would produce intense X-radiation as it is heated to millions of degrees. The X-rays would diminish in a characteristic manner as the hot gas spiraled inward.

In the past few years, Chandra and other astronomical satellites have identified several suspected cases of a supermassive black hole ripping apart a nearby star. This newly discovered episode of cosmic, black-hole-induced violence is different because it has been associated with a much smaller galaxy than these other cases.

The so-called dwarf galaxy is located in the galaxy cluster Abell 1795, about 800 million light-years from Earth. It contains about 700 million stars, far less than a typical galaxy like the Milky Way, which has between 200 and 400 billion stars. Moreover, the black hole in this dwarf galaxy may be only be a few hundred thousand times as massive as the Sun, making it ten times less massive than the galaxy's supermassive black hole, and placing it in what astronomers call an "intermediate mass black hole" category.

This video is not supported by your browser at this time.

Watch an animated tour of galaxy cluster Abell 1795.

"Scientists have been searching for these intermediate mass black holes for decades," said Davide Donato of NASA's Goddard Space Flight Center (GSFC) in Greenbelt, Md., who led a separate team of researchers. "We have lots of evidence for small black holes and very big ones, but these medium-sized ones have been tough to pin down."

The evidence for a star being ripped apart by the dwarf galaxy's black hole came from combing through Chandra data that had been taken over several years. Because Abell 1795 is a target that Chandra observes regularly to help calibrate its instruments, the researchers had access to an unusually large reservoir of data on this object.

"We are very lucky that we had so much data on Abell 1795 over such a long period of time," said Donato's co-author Brad Cenko, also of GSFC. "Without that, we could never have uncovered this special event."

The dwarf galaxy's location in a galaxy cluster also makes it a potential victim of another type of cosmic violence. Because galaxy clusters are crowded with galaxies, it's possible that a large number of stars have been pulled away from the dwarf galaxy by gravitational interactions with another galaxy in the past, a process called tidal stripping.

"It looks like the stars in this galaxy not only need to worry about the black hole in the center," said Makysm's co-author Melville Ulmer of Northwestern University in Evanston, Ill. "They might also be stolen away on the outside by gravity from a passing galaxy."

Astronomers believe that intermediate mass black holes may be the "seeds" that ultimately formed the supermassive black holes in the centers of galaxies like the Milky Way. Finding additional nearby examples should teach us about how these primordial galaxies from the early universe grew and evolved over cosmic time.

Some of the additional clues to this star attack came from NASA's Extreme Ultraviolet Explorer that picked up a very bright ultraviolet source in 1998, which could have marked a time just after the star was initially torn apart. A flare in X-rays may have also been detected with ESA's XMM-Newton satellite in 2000.

Peter Maksym presented these results today at the 223rd meeting of the American Astronomical Society meeting in Washington, DC on behalf of his team. A paper describing their work is available online and was published in the November 1, 2013, issue of the Monthly Notices of the Royal Astronomical Society. The paper by Davide Donato and his colleagues on this same event is available online and was accepted for publication in The Astrophysical Journal.

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User comments : 31

"Students using astrophysical textbooks remain essentially ignorant of even the existence of plasma concepts, despite the fact that some of them have been known for half a century. The conclusion is that astrophysics is too important to be left in the hands of astrophysicists who have gotten their main knowledge from these textbooks. Earthbound and space telescope data must be treated by scientists who are familiar with laboratory and magnetospheric physics and circuit theory, and of course with modern plasma theory." Hannes Alfven

Being that the data is being treated by clueless metaphysicists, we get abominations of science such as these "monsters devouring" stars.

Students using astrophysical textbooks remain essentially ignorant of even the existence of plasma concepts, despite the fact that some of them have been known for half a century

Ironic. You're quoting a half century old statement that has been obsolete for half a century, about class cirriculum that was half a century out of date at that time, from a guy that still refused to accept relativity half a century after it became accepted by everyone else. It's like the frying pan quoting the kettle when it called the pot black.

One article calls a 100k black hole as "Super Massive" the other calls it "Intermediate". I just wish astrophysicists would make up their minds what they want the ranges to represent for each term, and stick to it.

Zephir_fan

Ironic. You're quoting a half century old statement that has been obsolete for half a century, about class cirriculum that was half a century out of date at that time, from a guy that still refused to accept relativity half a century after it became accepted by everyone else.

...discoveries from in situ observations of real plasma which DIRECTLY contradict and are not predicted by "standard" models. Please note the questions posed at the bottom of the article written 4 WEEKS AGO."Why are electron acoustic waves and the associated double layers formed? Why do double layers occur in streams of thousands? What conditions allow such large electric potential differences to exist? What drivers of the magnetospheric dynamics can also be found in other astrophysical systems?"

So not too swift, why would this "not out of date" astrophysicist ask such BASIC questions about plasma behavior? Fail

lol, those aren't basic questions. If you think those are basic, then feel free to write the guy an email and explain the answers to him.

Don't forget to call him a moron, just to make your point. These scientist guys need to be put in their place.

If you want a serious reply, then post some serious comments, and do a little bit of reading in your spare time. Learn what the basics are, then maybe you'll understand the article you linked to. That was a good article though. I obviously have a much deeper science vocabulary than you, and I had to do several cross references to follow along with that article. My guess is that you're too lazy to do that.

lol, those aren't basic questions. If you think those are basic, then feel free to write the guy an email and explain the answers to him.

They are basic, given you ask the right scientist. And it's not his fault, he just can't think for himself as all the critical thinkers are weeded out of the graduate programs. He can only see it from the "standard" theory POV, you know the POV based on "models we know to be wrong" but which contrary to your claims are still being used. If they were using the particle/circuit models Alfven was a proponent of then the electric DL's, electric potential differences, and other system dynamics would be obvious. If you or others would have ever read any of the papers here;http://www.plasma...ers.html...you will see these questions have already been addressed by those who treat the plasma with the proper models. "In order to understand the phenomena in a certain plasma region, it is necessary to map not only the magnetic but also the electric field and the electric currents." Hannes Alfven, Nobel Laureate

This paper explains why such questions are perplexing to astrophysicists but less so to those who understand the Kirchoff's circuit laws that drive plasma processes. Astrophysicists should be properly trained in aspects of electrical engineering to understand these plasma processes.

It bears repeating;"Students using astrophysical textbooks remain essentially ignorant of even the existence of plasma concepts, despite the fact that some of them have been known for half a century..."

Although these are not basic to laymen, for someone who is tasked to study plasma as their career, those are basic elementary questions.

"After all, to get the whole universe totally wrong in the face of clear evidence for over 75 years merits monumental embarrassment and should induce a modicum of humility." Halton Arp

Bears repeating: cantdrive85 believes that a theory originally put forward by Velikovsky, which suggests that Saturn was once the centre of the solar system based solely on drawings he saw on a cave wall, is more credible than theories which have been built over centuries and form the basis of our scientific understanding.

The same can be said about epicycles, theory built over centuries... The basis of our scientific understanding is the laws and fundamental rules of nature and using the scientific method, not the theories.

The "rock art" is data, scientific method suggests all data is included especially when the data paints a coherent picture. Here is a whole page of data which paints that coherent picture;http://www.plasma...rth.html

Velikovsky's theory I agree is totally preposterous to your worldview, the mechanics of the gravity only universe of the standard theory totally precludes the possibility of a Velikovskyian POV. The Electric Universe/PC isn't so averse of such mechanics, driven by EM and not the incomparably weak gravitational force. Oddly enough, once again the combination of the above mentioned theories continues to paint a coherent worldview that is also supported by the human history from cave art to mythology and religion, culture, etc.

What are you on about now? Part gobbly gook, part mysticism. You're almost as bad as Scooter.

The "rock art" is data,

No, it's art:

noun 1.the expression or application of human creative skill and imagination, typically in a visual form such as painting or sculpture, producing works to be appreciated primarily for their beauty or emotional power.

Data is:

noun 1. facts and statistics collected together for reference or analysis.

The "fact" ancient people painted on walls does not mean much beyond people like to paint on walls.

If you really understood the difference, you wouldn't keep repeating that silly statement. You lack a basic understanding of electromagnetic field theory. I know it's a waste of electrons to suggest this, but you could try to following text:

This is an introductory course in electromagnetic field theory text book, used at MIT. If you haven't had trig. and calculus, then it's going to look like a foriegn language to you, but that can't be helped.

Just skip to chapter 2, and look up section 2-5 "The Electrical Potential" and associated discussion of work and equipotential spheres. This is why an electric field cannot produce the eliptical keplarian orbits we observe accross the entire observable universe. It breaks the laws conservation of energy to suggest such a system would be stable

Were way beyond simple electrostatics to explain the remarkably complex nature of plasma

No, cantdrive, plasma does not defy the rules of electric fields. I knew you wouldn't bother looking at the textbook, and you wouldn't understand it if you did look at it.

That link you posted is crazy crackpot stuff. That guy believes in creation and he proposes what he calls the "Devine Force" which replaces both relativity and quantum theory, as well as the standard model of atoms. He says that the earth (and all solid bodies) are expanding and losing mass, which explains why biblical people lived 900 years, since there was more oxygen near the surface when the Earth was smaller. Since the earth is expanding, it has stretch marks, which the government is keeping secret (he says they use them to hide things like submarine bases.) I think you should keep quoting him. You can now dismiss all of modern physics, not just GR and EFT.

Newton was a creationist as well, and he believed crazy crackpot stuff too... I guess we should throw the baby out with the bathwater. BTW, I'm not a creationist and your right, plasma doesn't defy the rules of electric fields but field aligned EFs produce unique phenomena not described in that textbook. There is a great deal of evidence which supports the expanding Earth theory, not to mention Arp observations of quasars and other expanding objects in the cosmos.http://www.halton..._gravity

But you got it all figured out, that's why you have such a complete, consistent view of the cosmos of which we can only see 4% of it.

If Snowden can break his way into the NSA, surely you can manage to fake your way into undergraduate and then graduate physics long enough to expose them from the inside. Go for it cantdrive. Show us, from the inside, after you get your doctorate, how everyone is all plotting against a scientist none of us have heard of or care about because of how irrelevant he is to modern science.

Why that's a revealing tidbit from cantdrive. He not only ascribes to the EU fantasy, he also believes in the expanding Earth theory (look up S. Warren Carey among others) and Halton Arp's tired light theory. That must mean you also ascribe to O. Manual's Iron Sun theory and maybe even Lavoisier's Caloric Aether theory or Hoyle's Steady State theory?

So, in other words, you are a contrarian. If most scientists believe in something, you reflexively default to a "I don't believe it" position. No wonder you argue against global warming! An interesting psychological study indeed!

I must check with the psychology department to see if one of the students there would find this phenomena interesting as a thesis subject. I wonder cantdrive, would you agree to take part of such a study, if a student is interested?

Ironic. You're quoting a half century old statement that has been obsolete for half a century, about class cirriculum that was half a century out of date at that time, from a guy that still refused to accept relativity half a century after it became accepted by everyone else. It's like the frying pan quoting the kettle when it called the pot black.

GSwift7, if there was a WAY to give you 100 stars, i would! LOL

@Cantdrive

clear evidence for over 75 years

yeah... clear evidence that the EU/PU hypothesis is dead and buried! EU/PU is a dead hypothesis based upon a crackpot idea. deal with iteven your EU/PU couldnt fully describe the hex-storm on Saturn though fluid dynamics perfectly replicated it!

@MaggnusLet me know how that works out! i would LOVE too see their results!

Although I would agree contrarian, as far as "believing" in anything, no. From my POV, I see the EU offers the most comprehensive cosmology yet all these others you mention plus many more offer nuggets of wisdom in their own right. Even GR and all it's metaphysical mumbo jumbo has something to offer, just as epicycles and any number of other obsolete theories do. I like to keep my options open that the likely ultimate truth is some amalgam of many disparate theories. What I will do is refuse to do is claim "it's all settled" or get all whipped up in a tizzy because some flawed politicized "scientific model" predicts some outcome based upon erroneous "facts".

From my POV, I see the EU offers the most comprehensive cosmology yet all these others you mention plus many more offer nuggets of wisdom in their own right

@cantdrive85only in YOUR eyes: you follow EU/PU like a faith-IOW: nothing can prove your theories wrong (in YOUR eyes) even though you cannot offer proof and when confronted with overwhelming evidence contrary to your pet faith, you retreat to word salad mantra's that mean nothing to anyone with any common sense

you tend to relate PU/EU to EVERYTHING... and a theory that predicts every possible outcome predicts nothing

What I will do is refuse to do is claim "it's all settled" or get all whipped up in a tizzy because some flawed politicized "scientific model" predicts some outcome based upon erroneous "facts"

@cantdrive85really? You are calling some of the most tested, accurate theories in science a

flawed politicized "scientific model"

you PROVE the erroneous facts, and I guarantee that you will be more famous than Einstein ever thought of being... oh, right... you cant

in actuality you mean that it is not in line with your pet theoryor you dont like what it has to say because it directly refutes and/or proves your theory wrongand your theories have been proven wrong over and over... especially against GR and QMyou seem to completely ignore empirical data, PROOF

So, in other words, you are a contrarian. If most scientists believe in something, you reflexively default to a "I don't believe it" position. No wonder you argue against ______ _______! An interesting psychological study indeed

Oh, for crying out loud, don't name the Subject That Cannot be Named in this section. You'll attract the denizens of that section of the web site and it will take weeks to get rid of them again.

Read through the list of 6 traits of the phenotype and tell me he doesn't meet more than three of them (only three are needed for diagnosis). I'm interested to see if you agree with me regarding which of the 6 apply. Granted, online posts aren't really a good thing to judge by. He probably doesn't act so obnoxious in real life.

I'm interested to see if you agree with me regarding which of the 6 apply

@GSwift7ok... I say 1, 2, and 6 for sure, and demonstrations of 4 as well, although his demonstrations are usually just hostility in the posts.And 5 as there is no remorse

He probably doesn't act so obnoxious in real life.

I am not so sure about this one...maybe not so overtly obnoxious, but I think there is a serious notion by anyone around him that there are issues that need to be addressed, and that meds & counseling may be needed for long term care!see

From my POV, I see the EU offers the most comprehensive cosmology yet all these others you mention plus many more offer nuggets of wisdom in their own right

So that's three, and maybe that fourth one we don't know about, but it doesn't matter. But hey, that's just my amature opinion. I know about as much about it as he knows about electric field theory, so not much.

@GSwift7i am not so sure about this... he gets really irritated when you call him out about his theory, and gets verbally aggressive. i was just called a liar in this thread by himhttp://phys.org/n...ggs.htmli am not so sure he realises that he is being spanked, really.i think HE is of the opinion that he is correct, and he cannot actually SEE that he has been effectively refuted and proven wrong. like his comments in the Cassini/Saturn thread about the storm shape.

and he cannot actually SEE that he has been effectively refuted and proven wrong.

Only in your mind, as stated previously if I have been "proven" wrong NASA wouldn't consider it a "mystery". Nothing is "refuted" or "proven" in these comment threads contrary to your claims. All this discussion you guys are having still fall into the list of fallacious arguments, the only style you guys employ. Rubes!

Only in your mind, as stated previously if I have been "proven" wrong NASA wouldn't consider it a "mystery". Nothing is "refuted" or "proven" in these comment threads contrary to your claims

@Cantreadactually, I argued that the simple method using hydrodynamics better represented the action of Saturn's storm than the dicotron instabilities, as your theory was overly complex and did not effectively represent the design shownThen you argued about your EU being more representative of reality than QM and GR/SR. And I said

having a web-site doesn't make you an authority any more than standing in a garage makes you a Cadillac

of which I still stand behind.Especially as QM and GR/SR are the most tested and effective theories that ever existed.

Just because you THINK that your EU is valid, does not make said assumption true.

You have NO empirical data, and when you reference anything, you reference plasma physics, of which you apply it to things improperly or plain WRONG

Nothing is "refuted" or "proven" in these comment threads contrary to your claims

and i am saying that i used science and common sense to prove a point, of which i was pretty successful!you used excess verbiage, techno-jargon and repetitious arguments that did not apply to somehow come to a conclusion which was not supported, while using a hypothesis (the EU) that is not valid, as it is not peer reviewed, nor is it even effective or even SLIGHTLY capable of replacing QM.

you talked in circles using invalid arguments.you only proved yourself wrong.

and as for the stuff posted above between GSwift, Maggnus and i...truth bothering you?why else would you say

How in the world can I put words in your mouth when Maggnuts dick is already there?

Only in your mind, as stated previously if I have been "proven" wrong NASA wouldn't consider it a "mystery". Nothing is "refuted" or "proven" in these comment threads contrary to your claims

Nah, I used basic fundamentals to refute your pet theory. Nothing fancy, just basic field laws and some trigonometry. I linked directly to a first year college text book to show the math. Arguing against that, as though it is disputable, would be like saying that 2 and 2 don't equal 4.

@GSwiftthe above direct quote is what i meant by #4 and his lashin out at being spanked

Yeah, you're right. I'll go for 'yes' on number 4 as well.

The sad part is that he has worked so hard to build up the persona he uses here. It will be difficult for him to give it up now, no matter how obvious it is to him that it's a broken fantasy. He won't be able to abandon the identity, no matter how broken it is, or how easy it would be to just make a new name and pretend to be a new guy, or stop comments

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